An Improved Approach for Estimating Product Performance Based on the Capability Index C(pmk)

Abstract

In this article, we construct an improved procedure for estimating the process capability index C(pmk). We propose a new Cpmk lower-bound approach based on the GCI concept, and compare it with other existing methods. Based on the comparison results, we conclude with a recommendation, and construct a step-by-step procedure for the recommended approach to estimate the actual process capability Cpmk for various sample sizes. The lower bound attended by our recommended approach, indeed, improves other existing lower bound methods. We also investigate a real-world application to illustrate how we could apply the recommended approach to the actual manufacturing processes.